Generally, you need earned income to contribute to an IRA — unearned income like dividends, interest, rental income, or Social Security doesn't qualify. However, there is an important exception: the spousal IRA. If you're married and file jointly, a working spouse can contribute to an IRA on behalf of a non-working spouse, up to the full IRA limit ($7,000 in 2024), as long as the working spouse has enough earned income to cover both contributions. This allows a stay-at-home spouse to build retirement savings even without their own income. You cannot contribute to a traditional IRA after age 73 once RMDs must begin, but Roth IRAs have no age cutoff.